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<H1 class="no-header">curs_attr 3x</H1>
<PRE>
<STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>                                                    <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>




</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE>
       <STRONG>attr_get</STRONG>, <STRONG>wattr_get</STRONG>, <STRONG>attr_set</STRONG>, <STRONG>wattr_set</STRONG>, <STRONG>attr_off</STRONG>, <STRONG>wattr_off</STRONG>, <STRONG>attr_on</STRONG>,
       <STRONG>wattr_on</STRONG>, <STRONG>attroff</STRONG>, <STRONG>wattroff</STRONG>, <STRONG>attron</STRONG>, <STRONG>wattron</STRONG>, <STRONG>attrset</STRONG>, <STRONG>wattrset</STRONG>, <STRONG>chgat</STRONG>,
       <STRONG>wchgat</STRONG>, <STRONG>mvchgat</STRONG>, <STRONG>mvwchgat</STRONG>, <STRONG>color_set</STRONG>, <STRONG>wcolor_set</STRONG>, <STRONG>standend</STRONG>, <STRONG>wstandend</STRONG>,
       <STRONG>standout</STRONG>, <STRONG>wstandout</STRONG> - <STRONG>curses</STRONG> character and window attribute control
       routines


</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE>
       <STRONG>#include</STRONG> <STRONG>&lt;curses.h&gt;</STRONG>

       <STRONG>int</STRONG> <STRONG>attr_get(attr_t</STRONG> <STRONG>*</STRONG><EM>attrs</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <STRONG>*</STRONG><EM>pair</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>wattr_get(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>attr_t</STRONG> <STRONG>*</STRONG><EM>attrs</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <STRONG>*</STRONG><EM>pair</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>attr_set(attr_t</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>wattr_set(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>attr_t</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>

       <STRONG>int</STRONG> <STRONG>attr_off(attr_t</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>wattr_off(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>attr_t</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>attr_on(attr_t</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>wattr_on(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>attr_t</STRONG> <EM>attrs</EM><STRONG>,</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>

       <STRONG>int</STRONG> <STRONG>attroff(int</STRONG> <EM>attrs);</EM>
       <STRONG>int</STRONG> <STRONG>wattroff(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>attrs</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>attron(int</STRONG> <EM>attrs</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>wattron(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>attrs</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>attrset(int</STRONG> <EM>attrs</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>wattrset(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>attrs</EM><STRONG>);</STRONG>

       <STRONG>int</STRONG> <STRONG>chgat(int</STRONG> <EM>n</EM><STRONG>,</STRONG> <STRONG>attr_t</STRONG> <EM>attr</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>wchgat(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG>
             <STRONG>int</STRONG> <EM>n</EM><STRONG>,</STRONG> <STRONG>attr_t</STRONG> <EM>attr</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>mvchgat(int</STRONG> <EM>y</EM><STRONG>,</STRONG> <STRONG>int</STRONG> <EM>x</EM><STRONG>,</STRONG>
             <STRONG>int</STRONG> <EM>n</EM><STRONG>,</STRONG> <STRONG>attr_t</STRONG> <EM>attr</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>mvwchgat(WINDOW</STRONG> <STRONG>*</STRONG><EM>win,</EM> <EM>int</EM> <EM>y,</EM> <EM>int</EM> <EM>x</EM><STRONG>,</STRONG>
             <STRONG>int</STRONG> <EM>n,</EM> <STRONG>attr_t</STRONG> <EM>attr</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>const</STRONG> <STRONG>void</STRONG> <STRONG>*</STRONG><EM>opts</EM><STRONG>);</STRONG>

       <STRONG>int</STRONG> <STRONG>color_set(short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>void*</STRONG> <EM>opts</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>wcolor_set(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>,</STRONG> <STRONG>short</STRONG> <EM>pair</EM><STRONG>,</STRONG> <STRONG>void*</STRONG> <EM>opts);</EM>

       <STRONG>int</STRONG> <STRONG>standend(void);</STRONG>
       <STRONG>int</STRONG> <STRONG>wstandend(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>);</STRONG>
       <STRONG>int</STRONG> <STRONG>standout(void);</STRONG>
       <STRONG>int</STRONG> <STRONG>wstandout(WINDOW</STRONG> <STRONG>*</STRONG><EM>win</EM><STRONG>);</STRONG>


</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE>
       These  routines  manipulate the current attributes of the named window,
       which then apply to all characters that are  written  into  the  window
       with  <STRONG>waddch</STRONG>,  <STRONG>waddstr</STRONG>  and  <STRONG>wprintw</STRONG>.  Attributes are a property of the
       character, and move with the character through any  scrolling  and  in-
       sert/delete  line/character  operations.   To the extent possible, they
       are displayed as appropriate modifications to the graphic rendition  of
       characters put on the screen.

       These  routines do not affect the attributes used when erasing portions
       of the window.  See <STRONG><A HREF="curs_bkgd.3x.html">curs_bkgd(3x)</A></STRONG> for functions which  modify  the  at-
       tributes used for erasing and clearing.

       Routines  which  do  not have a <STRONG>WINDOW*</STRONG> parameter apply to <STRONG>stdscr</STRONG>.  For
       example, <STRONG>attr_set</STRONG> is the <STRONG>stdscr</STRONG> variant of <STRONG>wattr_set</STRONG>.


</PRE><H3><a name="h3-Window-attributes">Window attributes</a></H3><PRE>
       There are two sets of functions:

       <STRONG>o</STRONG>   functions for manipulating the window attributes  and  color:  <STRONG>wat-</STRONG>
           <STRONG>tr_set</STRONG> and <STRONG>wattr_get</STRONG>.

       <STRONG>o</STRONG>   functions  for manipulating only the window attributes (not color):
           <STRONG>wattr_on</STRONG> and <STRONG>wattr_off</STRONG>.

       The <STRONG>wattr_set</STRONG> function sets the current attributes of the given  window
       to <EM>attrs</EM>, with color specified by <EM>pair</EM>.

       Use <STRONG>wattr_get</STRONG> to retrieve attributes for the given window.

       Use  <STRONG>attr_on</STRONG>  and  <STRONG>wattr_on</STRONG>  to turn on window attributes, i.e., values
       OR'd together in <EM>attr</EM>, without affecting  other  attributes.   Use  <STRONG>at-</STRONG>
       <STRONG>tr_off</STRONG>  and  <STRONG>wattr_off</STRONG> to turn off window attributes, again values OR'd
       together in <EM>attr</EM>, without affecting other attributes.


</PRE><H3><a name="h3-Legacy-window-attributes">Legacy window attributes</a></H3><PRE>
       The X/Open window attribute routines which <EM>set</EM> or <EM>get</EM>, turn <EM>on</EM>  or  <EM>off</EM>
       are extensions of older routines which assume that color pairs are OR'd
       into the attribute parameter.  These newer routines use similar  names,
       because X/Open simply added an underscore (<STRONG>_</STRONG>) for the newer names.

       The <STRONG>int</STRONG> datatype used in the legacy routines is treated as if it is the
       same size as <STRONG>chtype</STRONG> (used by <STRONG><A HREF="curs_addch.3x.html">addch(3x)</A></STRONG>).  It holds the common video at-
       tributes  (such  as  bold,  reverse),  as well as a few bits for color.
       Those bits correspond to the <STRONG>A_COLOR</STRONG> symbol.  The <STRONG>COLOR_PAIR</STRONG> macro pro-
       vides  a value which can be OR'd into the attribute parameter.  For ex-
       ample, as long as that value fits into the  <STRONG>A_COLOR</STRONG>  mask,  then  these
       calls produce similar results:

           attrset(A_BOLD | COLOR_PAIR(<EM>pair</EM>));
           attr_set(A_BOLD, <EM>pair</EM>, NULL);

       However, if the value does not fit, then the <STRONG>COLOR_PAIR</STRONG> macro uses only
       the bits that fit.  For example, because in ncurses <STRONG>A_COLOR</STRONG>  has  eight
       (8) bits, then <STRONG>COLOR_PAIR(</STRONG><EM>259</EM><STRONG>)</STRONG> is 4 (i.e., 259 is 4 more than the limit
       255).

       The <STRONG>PAIR_NUMBER</STRONG> macro extracts a pair number from an <STRONG>int</STRONG>  (or  <STRONG>chtype</STRONG>).
       For  example,  the <EM>input</EM> and <EM>output</EM> values in these statements would be
       the same:

           int value = A_BOLD | COLOR_PAIR(<EM>input</EM>);
           int <EM>output</EM> = PAIR_NUMBER(value);

       The <STRONG>attrset</STRONG> routine is a legacy feature predating SVr4 curses but  kept
       in X/Open Curses for the same reason that SVr4 curses kept it: compati-
       bility.

       The remaining <STRONG>attr</STRONG>* functions operate exactly  like  the  corresponding
       <STRONG>attr_</STRONG>*  functions,  except  that they take arguments of type <STRONG>int</STRONG> rather
       than <STRONG>attr_t</STRONG>.

       There is no corresponding <STRONG>attrget</STRONG> function as such  in  X/Open  Curses,
       although ncurses provides <STRONG>getattrs</STRONG> (see <STRONG><A HREF="curs_legacy.3x.html">curs_legacy(3x)</A></STRONG>).


</PRE><H3><a name="h3-Change-character-rendition">Change character rendition</a></H3><PRE>
       The  routine  <STRONG>chgat</STRONG> changes the attributes of a given number of charac-
       ters starting at the current cursor location of <STRONG>stdscr</STRONG>.   It  does  not
       update  the cursor and does not perform wrapping.  A character count of
       -1 or greater than the remaining  window  width  means  to  change  at-
       tributes  all the way to the end of the current line.  The <STRONG>wchgat</STRONG> func-
       tion generalizes this to any window; the <STRONG>mvwchgat</STRONG> function does a  cur-
       sor move before acting.

       In  these  functions, the color <EM>pair</EM> argument is a color-pair index (as
       in the first argument of <STRONG>init_pair</STRONG>, see <STRONG><A HREF="curs_color.3x.html">curs_color(3x)</A></STRONG>).


</PRE><H3><a name="h3-Change-window-color">Change window color</a></H3><PRE>
       The routine <STRONG>color_set</STRONG> sets the current color of the given window to the
       foreground/background  combination  described by the color <EM>pair</EM> parame-
       ter.


</PRE><H3><a name="h3-Standout">Standout</a></H3><PRE>
       The routine <STRONG>standout</STRONG> is the same as  <STRONG>attron(A_STANDOUT)</STRONG>.   The  routine
       <STRONG>standend</STRONG>  is  the  same as <STRONG>attrset(A_NORMAL)</STRONG> or <STRONG>attrset(0)</STRONG>, that is, it
       turns off all attributes.

       X/Open does not mark these "restricted", because

       <STRONG>o</STRONG>   they have well established legacy use, and

       <STRONG>o</STRONG>   there is no ambiguity about the way the attributes  might  be  com-
           bined with a color pair.


</PRE><H2><a name="h2-VIDEO-ATTRIBUTES">VIDEO ATTRIBUTES</a></H2><PRE>
       The following video attributes, defined in <STRONG>&lt;curses.h&gt;</STRONG>, can be passed to
       the routines <STRONG>attron</STRONG>, <STRONG>attroff</STRONG>, and <STRONG>attrset</STRONG>, or OR'd with the  characters
       passed to <STRONG>addch</STRONG> (see <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>).

              <EM>Name</EM>           <EM>Description</EM>
              -----------------------------------------------------------------
              <STRONG>A_NORMAL</STRONG>       Normal display (no highlight)
              <STRONG>A_STANDOUT</STRONG>     Best highlighting mode of the terminal.
              <STRONG>A_UNDERLINE</STRONG>    Underlining
              <STRONG>A_REVERSE</STRONG>      Reverse video
              <STRONG>A_BLINK</STRONG>        Blinking
              <STRONG>A_DIM</STRONG>          Half bright
              <STRONG>A_BOLD</STRONG>         Extra bright or bold
              <STRONG>A_PROTECT</STRONG>      Protected mode
              <STRONG>A_INVIS</STRONG>        Invisible or blank mode
              <STRONG>A_ALTCHARSET</STRONG>   Alternate character set
              <STRONG>A_ITALIC</STRONG>       Italics (non-X/Open extension)
              <STRONG>A_CHARTEXT</STRONG>     Bit-mask to extract a character
              <STRONG>A_COLOR</STRONG>        Bit-mask to extract a color (legacy routines)

       These  video  attributes are supported by <STRONG>attr_on</STRONG> and related functions
       (which also support the attributes recognized by <STRONG>attron</STRONG>, etc.):

              <EM>Name</EM>            <EM>Description</EM>
              -----------------------------------------
              <STRONG>WA_HORIZONTAL</STRONG>   Horizontal highlight
              <STRONG>WA_LEFT</STRONG>         Left highlight
              <STRONG>WA_LOW</STRONG>          Low highlight
              <STRONG>WA_RIGHT</STRONG>        Right highlight
              <STRONG>WA_TOP</STRONG>          Top highlight
              <STRONG>WA_VERTICAL</STRONG>     Vertical highlight

       The return values of many of these routines are  not  meaningful  (they
       are  implemented  as macro-expanded assignments and simply return their
       argument).  The SVr4 manual page claims (falsely) that  these  routines
       always return <STRONG>1</STRONG>.


</PRE><H2><a name="h2-NOTES">NOTES</a></H2><PRE>
       These functions may be macros:

              <STRONG>attroff</STRONG>,  <STRONG>wattroff</STRONG>, <STRONG>attron</STRONG>, <STRONG>wattron</STRONG>, <STRONG>attrset</STRONG>, <STRONG>wattrset</STRONG>, <STRONG>standend</STRONG>
              and <STRONG>standout</STRONG>.

       Color pair values can only be OR'd with attributes if the  pair  number
       is less than 256.  The alternate functions such as <STRONG>color_set</STRONG> can pass a
       color pair value directly.  However, ncurses ABI 4 and 5 simply OR this
       value  within  the  alternate functions.  You must use ncurses ABI 6 to
       support more than 256 color pairs.


</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE>
       X/Open Curses is largely based  on  SVr4  curses,  adding  support  for
       "wide-characters"  (not  specific to Unicode).  Some of the X/Open dif-
       ferences from SVr4 curses address the way video attributes can  be  ap-
       plied  to  wide-characters.   But aside from that, <STRONG>attrset</STRONG> and <STRONG>attr_set</STRONG>
       are similar.  SVr4 curses provided the basic features for  manipulating
       video  attributes.  However, earlier versions of curses provided a part
       of these features.

       As seen in 2.8BSD, curses assumed 7-bit characters,  using  the  eighth
       bit  of  a byte to represent the <EM>standout</EM> feature (often implemented as
       bold and/or reverse video).  The BSD curses library provided  functions
       <STRONG>standout</STRONG>  and  <STRONG>standend</STRONG> which were carried along into X/Open Curses due
       to their pervasive use in legacy applications.

       Some terminals in the 1980s  could  support  a  variety  of  video  at-
       tributes,  although the BSD curses library could do nothing with those.
       System V (1983) provided an improved curses library.  It defined the <STRONG>A_</STRONG>
       symbols  for  use  by  applications to manipulate the other attributes.
       There are few useful references for the chronology.

       Goodheart's book <EM>UNIX</EM> <EM>Curses</EM> <EM>Explained</EM> (1991)  describes  SVr3  (1987),
       commenting on several functions:

       <STRONG>o</STRONG>   the  <STRONG>attron</STRONG>,  <STRONG>attroff</STRONG>, <STRONG>attrset</STRONG> functions (and most of the functions
           found in SVr4 but not in BSD curses) were introduced by System V,

       <STRONG>o</STRONG>   the alternate character set feature with <STRONG>A_ALTCHARSET</STRONG> was added  in
           SVr2 and improved in SVr3 (by adding <STRONG>acs_map[]</STRONG>),

       <STRONG>o</STRONG>   <STRONG>start_color</STRONG>  and  related color-functions were introduced by System
           V.3.2,

       <STRONG>o</STRONG>   pads, soft-keys were added in SVr3, and

       Goodheart did not mention the background character or the <STRONG>cchar_t</STRONG> type.
       Those are respectively SVr4 and X/Open features.  He did mention the <STRONG>A_</STRONG>
       constants, but did not indicate their values.  Those were not the  same
       in different systems, even for those marked as System V.

       Different  Unix  systems  used  different  sizes  for the bit-fields in
       <STRONG>chtype</STRONG> for <EM>characters</EM> and <EM>colors</EM>, and took into account  the  different
       integer sizes (32-bit versus 64-bit).

       This  table  showing  the number of bits for <STRONG>A_COLOR</STRONG> and <STRONG>A_CHARTEXT</STRONG> was
       gleaned from the curses header files for various operating systems  and
       architectures.   The inferred architecture and notes reflect the format
       and size of the defined constants as well as clues such as  the  alter-
       nate  character  set implementation.  A 32-bit library can be used on a
       64-bit system, but not necessarily the reverse.

              <EM>Year</EM>   <EM>System</EM>        <EM>Arch</EM>    <EM>Color</EM>   <EM>Char</EM>   <EM>Notes</EM>
              ----------------------------------------------------------------
              1992   Solaris 5.2   32      6       17     SVr4 curses
              1992   HPUX 9        32      no      8      SVr2 curses
              1992   AIX 3.2       32      no      23     SVr2 curses
              1994   OSF/1 r3      32      no      23     SVr2 curses
              1995   HP-UX 10.00   32      6       16     SVr3 "curses_colr"
              1995   HP-UX 10.00   32      6       8      SVr4, X/Open curses
              1995   Solaris 5.4   32/64   7       16     X/Open curses
              1996   AIX 4.2       32      7       16     X/Open curses
              1996   OSF/1 r4      32      6       16     X/Open curses

              1997   HP-UX 11.00   32      6       8      X/Open curses
              2000   U/Win         32/64   7/31    16     uses <STRONG>chtype</STRONG>

       Notes:

          Regarding HP-UX,

          <STRONG>o</STRONG>   HP-UX 10.20 (1996) added support for 64-bit  PA-RISC  processors
              in 1996.

          <STRONG>o</STRONG>   HP-UX  10.30 (1997) marked "curses_colr" obsolete.  That version
              of curses was dropped with HP-UX 11.30 in 2006.

          Regarding OSF/1 (and Tru64),

          <STRONG>o</STRONG>   These used 64-bit hardware.  Like ncurses, the OSF/1 curses  in-
              terface is not customized for 32-bit and 64-bit versions.

          <STRONG>o</STRONG>   Unlike other systems which evolved from AT&amp;T code, OSF/1 provid-
              ed a new implementation for X/Open curses.

          Regarding Solaris,

          <STRONG>o</STRONG>   The initial release of Solaris was in 1992.

          <STRONG>o</STRONG>   The <EM>xpg4</EM> (X/Open) curses was developed by MKS from 1990 to 1995.
              Sun's copyright began in 1996.

          <STRONG>o</STRONG>   Sun updated the X/Open curses interface after 64-bit support was
              introduced in 1997, but did not modify the  SVr4  curses  inter-
              face.

          Regarding U/Win,

          <STRONG>o</STRONG>   Development  of  the  curses  library  began in 1991, stopped in
              2000.

          <STRONG>o</STRONG>   Color support was added in 1998.

          <STRONG>o</STRONG>   The library uses only <STRONG>chtype</STRONG> (no <STRONG>cchar_t</STRONG>).

       Once X/Open curses was adopted in the mid-1990s, the  constraint  of  a
       32-bit interface with many colors and wide-characters for <STRONG>chtype</STRONG> became
       a moot point.  The <STRONG>cchar_t</STRONG> structure (whose size and  members  are  not
       specified in X/Open Curses) could be extended as needed.

       Other interfaces are rarely used now:

       <STRONG>o</STRONG>   BSD  curses was improved slightly in 1993/1994 using Keith Bostic's
           modification to make the library 8-bit clean  for  <STRONG>nvi</STRONG>.   He  moved
           <EM>standout</EM> attribute to a structure member.

           The  resulting  4.4BSD curses was replaced by ncurses over the next
           ten years.

       <STRONG>o</STRONG>   U/Win is rarely used now.


</PRE><H2><a name="h2-EXTENSIONS">EXTENSIONS</a></H2><PRE>
       This implementation provides the <STRONG>A_ITALIC</STRONG> attribute for terminals which
       have  the  <STRONG>enter_italics_mode</STRONG> (<STRONG>sitm</STRONG>) and <STRONG>exit_italics_mode</STRONG> (<STRONG>ritm</STRONG>) capa-
       bilities.  Italics are not mentioned in X/Open Curses.  Unlike the oth-
       er  video attributes, <STRONG>A_ITALIC</STRONG> is unrelated to the <STRONG>set_attributes</STRONG> capa-
       bilities.  This  implementation  makes  the  assumption  that  <STRONG>exit_at-</STRONG>
       <STRONG>tribute_mode</STRONG> may also reset italics.

       Each  of  the functions added by XSI Curses has a parameter <EM>opts</EM>, which
       X/Open Curses still (after more than twenty  years)  documents  as  re-
       served for future use, saying that it should be <STRONG>NULL</STRONG>.  This implementa-
       tion uses that parameter in ABI 6 for the functions which have a color-
       pair parameter to support <EM>extended</EM> <EM>color</EM> <EM>pairs</EM>:

       <STRONG>o</STRONG>   For  functions  which modify the color, e.g., <STRONG>wattr_set</STRONG>, if <EM>opts</EM> is
           set it is treated as a pointer to <STRONG>int</STRONG>, and used to  set  the  color
           pair instead of the <STRONG>short</STRONG> <EM>pair</EM> parameter.

       <STRONG>o</STRONG>   For functions which retrieve the color, e.g., <STRONG>wattr_get</STRONG>, if <EM>opts</EM> is
           set it is treated as a pointer to <STRONG>int</STRONG>, and  used  to  retrieve  the
           color pair as an <STRONG>int</STRONG> value, in addition retrieving it via the stan-
           dard pointer to <STRONG>short</STRONG> parameter.

       The remaining functions which have <EM>opts</EM>, but do not  manipulate  color,
       e.g., <STRONG>wattr_on</STRONG> and <STRONG>wattr_off</STRONG> are not used by this implementation except
       to check that they are <STRONG>NULL</STRONG>.


</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE>
       These functions are supported in the XSI Curses standard, Issue 4.  The
       standard  defined  the dedicated type for highlights, <STRONG>attr_t</STRONG>, which was
       not defined in SVr4 curses.  The functions taking <STRONG>attr_t</STRONG> arguments were
       not supported under SVr4.

       Very old versions of this library did not force an update of the screen
       when changing the attributes.  Use <STRONG>touchwin</STRONG>  to  force  the  screen  to
       match the updated attributes.

       The  XSI  Curses standard states that whether the traditional functions
       <STRONG>attron</STRONG>/<STRONG>attroff</STRONG>/<STRONG>attrset</STRONG> can manipulate attributes  other  than  <STRONG>A_BLINK</STRONG>,
       <STRONG>A_BOLD</STRONG>,  <STRONG>A_DIM</STRONG>, <STRONG>A_REVERSE</STRONG>, <STRONG>A_STANDOUT</STRONG>, or <STRONG>A_UNDERLINE</STRONG> is "unspecified".
       Under this implementation as well as SVr4 curses, these functions  cor-
       rectly  manipulate  all  other  highlights (specifically, <STRONG>A_ALTCHARSET</STRONG>,
       <STRONG>A_PROTECT</STRONG>, and <STRONG>A_INVIS</STRONG>).

       XSI Curses added these entry points:

              <STRONG>attr_get</STRONG>, <STRONG>attr_on</STRONG>, <STRONG>attr_off</STRONG>, <STRONG>attr_set</STRONG>, <STRONG>wattr_on</STRONG>, <STRONG>wattr_off</STRONG>, <STRONG>wat-</STRONG>
              <STRONG>tr_get</STRONG>, <STRONG>wattr_set</STRONG>

       The  new  functions are intended to work with a new series of highlight
       macros prefixed with <STRONG>WA_</STRONG>.  The older macros have direct counterparts in
       the newer set of names:

              <EM>Name</EM>            <EM>Description</EM>
              ------------------------------------------------------------
              <STRONG>WA_NORMAL</STRONG>       Normal display (no highlight)
              <STRONG>WA_STANDOUT</STRONG>     Best highlighting mode of the terminal.
              <STRONG>WA_UNDERLINE</STRONG>    Underlining
              <STRONG>WA_REVERSE</STRONG>      Reverse video
              <STRONG>WA_BLINK</STRONG>        Blinking
              <STRONG>WA_DIM</STRONG>          Half bright
              <STRONG>WA_BOLD</STRONG>         Extra bright or bold
              <STRONG>WA_ALTCHARSET</STRONG>   Alternate character set

       XSI  curses  does not assign values to these symbols, nor does it state
       whether or not they are related to the similarly-named A_NORMAL, etc.:

       <STRONG>o</STRONG>   The XSI curses standard specifies that each pair  of  corresponding
           <STRONG>A_</STRONG>  and  <STRONG>WA_</STRONG>-using functions operates on the same current-highlight
           information.

       <STRONG>o</STRONG>   However, in some implementations, those symbols have unrelated val-
           ues.

           For example, the Solaris <EM>xpg4</EM> (X/Open) curses declares <STRONG>attr_t</STRONG> to be
           an unsigned short integer (16-bits), while <STRONG>chtype</STRONG> is a unsigned in-
           teger  (32-bits).   The <STRONG>WA_</STRONG> symbols in this case are different from
           the <STRONG>A_</STRONG> symbols because they are used for a smaller  datatype  which
           does not represent <STRONG>A_CHARTEXT</STRONG> or <STRONG>A_COLOR</STRONG>.

           In this implementation (as in many others), the values happen to be
           the same because it simplifies copying information  between  <STRONG>chtype</STRONG>
           and <STRONG>cchar_t</STRONG> variables.

       The XSI standard extended conformance level adds new highlights <STRONG>A_HORI-</STRONG>
       <STRONG>ZONTAL</STRONG>, <STRONG>A_LEFT</STRONG>, <STRONG>A_LOW</STRONG>, <STRONG>A_RIGHT</STRONG>, <STRONG>A_TOP</STRONG>,  <STRONG>A_VERTICAL</STRONG>  (and  corresponding
       <STRONG>WA_</STRONG>  macros  for  each).  As of August 2013, no known terminal provides
       these highlights (i.e., via the <STRONG>sgr1</STRONG> capability).


</PRE><H2><a name="h2-RETURN-VALUE">RETURN VALUE</a></H2><PRE>
       All routines return the integer <STRONG>OK</STRONG> on success, or <STRONG>ERR</STRONG> on failure.

       X/Open does not define any error conditions.

       This implementation

       <STRONG>o</STRONG>   returns an error if the window pointer is null.

       <STRONG>o</STRONG>   returns an error if the color pair parameter for <STRONG>wcolor_set</STRONG> is out-
           side the range 0..COLOR_PAIRS-1.

       <STRONG>o</STRONG>   does  not  return an error if either of the parameters of <STRONG>wattr_get</STRONG>
           used for retrieving attribute or color-pair values is <STRONG>NULL</STRONG>.

       Functions with a "mv" prefix first  perform  a  cursor  movement  using
       <STRONG>wmove</STRONG>, and return an error if the position is outside the window, or if
       the window pointer is null.


</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE>
       <STRONG><A HREF="ncurses.3x.html">curses(3x)</A></STRONG>, <STRONG><A HREF="curs_addch.3x.html">curs_addch(3x)</A></STRONG>, <STRONG><A HREF="curs_addstr.3x.html">curs_addstr(3x)</A></STRONG>, <STRONG><A HREF="curs_bkgd.3x.html">curs_bkgd(3x)</A></STRONG>,
       <STRONG><A HREF="curs_printw.3x.html">curs_printw(3x)</A></STRONG>, <STRONG><A HREF="curs_variables.3x.html">curs_variables(3x)</A></STRONG>



                                                                 <STRONG><A HREF="curs_attr.3x.html">curs_attr(3x)</A></STRONG>
</PRE>
<div class="nav">
<ul>
<li><a href="#h2-NAME">NAME</a></li>
<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#h2-DESCRIPTION">DESCRIPTION</a>
<ul>
<li><a href="#h3-Window-attributes">Window attributes</a></li>
<li><a href="#h3-Legacy-window-attributes">Legacy window attributes</a></li>
<li><a href="#h3-Change-character-rendition">Change character rendition</a></li>
<li><a href="#h3-Change-window-color">Change window color</a></li>
<li><a href="#h3-Standout">Standout</a></li>
</ul>
</li>
<li><a href="#h2-VIDEO-ATTRIBUTES">VIDEO ATTRIBUTES</a></li>
<li><a href="#h2-NOTES">NOTES</a></li>
<li><a href="#h2-HISTORY">HISTORY</a></li>
<li><a href="#h2-EXTENSIONS">EXTENSIONS</a></li>
<li><a href="#h2-PORTABILITY">PORTABILITY</a></li>
<li><a href="#h2-RETURN-VALUE">RETURN VALUE</a></li>
<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li>
</ul>
</div>
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